Anti-VEGF therapy of wet age-related macular degeneration: analysis of patients lost to follow-up

Abstract

To study the reasons for patients receiving anti-VEGF therapy for «wet» age-related macular degeneration (wAMD) in clinical environment to cease monitoring in the clinic. This retrospective cohort study included patients with wAMD which received anti-VEGF therapy (ranibizumab, aflibercept) in the Ural State Medical University clinic from 2011 to 2019 (n=241). A subgroup of patients continuing treatment (n=90) was compared with a subgroup of lost to follow up patients (LTFU, n=151, 62.7%). Observation lasting less than 12 months was an exclusion criterion. Statistical analysis included a comparison of demographic and clinical data. The reasons for treatment discontinuation were determined using a phone survey. Characteristic for the LTFU subgroup were shorter duration of the follow-up (p<0.0001), lower number of intravitreal injections (p<0.0001), lower baseline (p<0.0001) and final best corrected visual acuity (p<0.0053) as well as higher values of therapy intensity coefficient (the ratio of the number of intravitreal injections to the duration of the follow-up, p<0.0001). According to the results of the phone survey, the following categories of LTFU were identified: ceased regular monitoring/treatment - 83 (55.0% of the LTFU subgroup), continued treatment in another clinic - 14 (9.3%), deceased - 18 (11.9%), status unknown - 36 (23.8%). The most common causes of LTFU were dissatisfaction with treatment results, financial burden and general comorbidities, which were named by 50, 27 and 17 respondents, respectively. In accordance with identified reasons for LTFU, we determined the directions for increasing the effectiveness of wAMD treatment: early diagnosis and start of treatment; using the most effective drugs and therapeutic regimens; increasing the availability of anti-VEGF therapy.